There are many situations in which hazardous gases may accumulate in dangerous concentrations. In such cases health and safety regulations and prudence both require a system capable of detecting accumulations of hazardous gases before a hazardous situation exists. For example, many industrial processes use highly flammable or poisonous gases. An industrial plant which uses such processes typically requires a gas detection system having gas sensors distributed throughout the plant and a central station which receives signals from the gas sensors. If one of the gas sensors detects an excessive amount of a hazardous gas then an alarm condition is triggered at the central station.
Such industrial gas detection systems are typically very expensive. The central stations typically include proprietary hardware which has limited upgradability.
Self-contained gas detection systems are also available. A self-contained gas detection system comprises a gas sensor, a battery a simple control circuit and an audible and/or visible alarm contained in a small housing. An example of such self-contained gas detectors are the carbon monoxide detectors and smoke detectors which are widely marketed for use in households and small businesses.
Industrial plants must typically have both built-in gas detection systems and portable self contained gas detectors. If the built-in system detects a troubling amount of a hazardous gas in the vicinity of a particular gas sensor then personnel may be dispatched to the area of the gas sensor in question with portable gas sensors. The portable gas sensors may be used to confirm the amount of hazardous gas detected and to locate the source of the hazardous gas. The management of such industrial plants typically have rigid policies in place which require measurements made by plant personnel to be carefully documented.
Gas sensors are available for detecting a wide range of hazardous gases. Sensors are available for detecting flammable gases, asphyxiating gases of various kinds, radioactive gases, gases containing certain toxins, and so on.
There is a need for a gas detection system which is less expensive to supply and configure than are typical built-in gas detection systems which are now available. There is also a need for gas detection systems which assist in the documentation of gas levels measured with portable gas detectors.